posted 9th December 2025
HMRC COP9 Investigations Explained: What Happens if You Receive a Contractual Disclosure Facility Letter
A COP9 letter from HMRC is one of the most serious civil investigation notices a taxpayer can receive. It means HMRC suspects deliberate tax fraud but is offering a chance to avoid criminal prosecution through full disclosure.
Under COP9, HMRC invites the taxpayer to enter the Contractual Disclosure Facility (CDF). Accepting requires a complete and accurate disclosure of all deliberate tax irregularities. Refusing significantly increases the risk of criminal investigation.
Many people mistakenly assume COP9 only applies to large businesses. In reality, individuals, landlords, contractors, and owner-managed businesses are frequently targeted.
Once accepted, the investigation can last 12–24 months or longer. HMRC will conduct detailed forensic analysis of bank accounts, businesses, property, and third-party information.
Get Urgent COP9 Investigation Advice Today
COP9 carries enormous legal consequences. Inaccurate disclosures, partial admissions, or misleading explanations can invalidate the protection from prosecution.
This is why unrepresented responses to COP9 are extremely dangerous. Every statement becomes part of a formal legal record.
With experienced handling, COP9 can conclude with:
- Civil settlement only
- Managed penalties
- No criminal record
- Long-term financial certainty
Without proper handling, the risk of criminal escalation rises sharply.
If you’re worried about an HMRC letter, an investigation, or undeclared income, you don’t need to face it alone.
At Tax Investigation Helpline, our independent experts deal with HMRC every single day and know exactly how to protect you from unnecessary penalties, stress, and escalation.
A confidential conversation with us can give you clarity and a clear plan of action within minutes. Speak to an advisor today, before responding to HMRC.
